不同米含量比例對味噌發酵之影響與味噌乾燥方法之探討

Abstract

分別以30，60及80％秈米製麴混合蒸熟大豆及9％食鹽進行味噌發酵四個月，粗蛋白含量隨米含量之增加而減少，還原糖含量則隨米含量之增加而明顯增加。發酵期間水分含量、乾物中蛋白質及游離胺基酸含量隨發酵時間之增加而增加，而PH值則隨發酵時間之增加而下降，色澤亦隨時間而加深。以發酵三個月之味嘈進行乾燥製粉時，除凍結乾燥外，皆產生明顯之褐變且所有乾粉皆易於吸濕結塊。以熟成味噌（含米量30％發酵三個月）直接添加經乾熱處理過之米穀粉作為助乾燥劑進行熱風乾燥時，乾燥速率隨添加量之提高而明顯上升，添加米穀粉40％時，其風味品質及色澤皆良好，且其吸濕性亦明顯下降。 Various percentages of rice in proportional to total weight of rice and soybean used for miso preparation, i. e., 30, 60 and 80% after cooking were subjected to koji making and miso preparation. Protein contents decreased and reducing sugar contents increased with increases of rice content used for miso preparation. During the fermentation period up to 4 months, moisture, protein and amino acid contents and color of the products increased while pH values of the products decreased with increases of fermentation time. When the aged miso products were dehydrated in a forced-air oven, significant browning of the products resulted in low sensory acceptance was observed. After dehydration and pulverization, the powders were hygroscopic. However, when the aged miso was previously mixed with various amounts of dry heat treated rice powder and dehydrated, the higher added rice powder the more rapid dehydration rate was achieved. An acceptable product with fine flavor, color and hygroscopic quality was obtained by addition of 40% of rice powder into the aged miso to facilitate dehydration and enhance miso powder production.